Graphic recording apparatus.



J. T. DEMPSTER.

GRAPHIG RECORDING APPARATUS.

APPLICATION FILED OUT. 20, 1913.

Patented Mar. 16, 1915.

LN in d A w r& m 0P 0 Bm '1 He t W n n s n H h STATES PATENT orrron.

JOHN T. :onmrsrnn, or scnnnncrnnr, m ex,. AssIeNon. 'ro GENERAL nnncrmc comrnmr, A. conromrro v on NEW YORK.

GRAPHIC nnconnmq -inrranarcs Specification of Letters fatenti ,atented Mar. 16, 1915.

Application filed October 20, 1913. Serial No. 796,107. 1

To all whom it may concern Be it known that I, J OHN T. DEMPSTER, a subject of the King of Great Britain, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Graphic Recording Apparatus, of which the following is a specification.

My invention relates to graphic recording apparatus and particularly to apparatus for recording electrical characteristics and quantities.

More particularly my invention relates to apparatus comprising in combination. with an electric meter a graphic recording instrument, and more specifically my invention relates to a'nelectric recording appa ratus in which a step by step record is imparted on a time actuated record sheet by a marking device whose movement is wholly or partially controlled by ah electric meter shaft.

The object of my invention is to generally improve the present construction of graphic recording apparatus.

More particularly the object of my invention is to provide a novel and improved form of actuating mechanism for the marking device of a recording apparatus of the type to which my invention relates.

Other objects of my invention will be aparent from a consideration of the following description of my improved graphic recording apparatus.

The features of my invention which I consider patentably novel aredefinitely in-.

dicated in the claims appended hereto.

The construction and mode of operation of an electrical recording apparatus embodying the novel features of my invention will be understood from the following description taken in connection with the accompanying drawings in which:

Figure 1 is a diagrammatic view of my improved type of graphic recording apparatus operatlvely connected to an electric meter, and Fig. 2 is a diagrammatic view of the same apparatus with a modified means for controlling the return of the marking device to its initialposition.

Referring first to Fig. 1 of the drawings, there is diagrammatically represented .an electric motor meter of the induction type. This meter-comprises a rotatable disk armature 5 secured to a pivoted shaft 6.- The disk armature is located within the influence of a potential coil 7 and a series coil 8 and its revolutions are damped in the usual manner by a permanent magnet 9. The revolutions of the armature 5 are thus directly proportional to the quantity of energy supplied to the translating devices 10.

The graphic recording apparatus comprises a record sheet 11 which is movably mounted on suitable rotatable drums. One of these drums 12. is shown in the drawings and is operatively connected to a clockwork mechanism 13. While I have illustrated in the drawings a clockwork mechanism for moving the drum 12, it will be understood that any constant speed driving mechanism,

shown in Fig. 1 of the drawings. The other 'end of the arm 14: is pivoted to an arm 28.

The arm 28 is rigidly secured to a pivoted shaft 16.

A coiled spring 29 is secured at one end to pin 17 and at the other end to the pivoted shaft 16, and when energized acts as a motive means for moving the marking device. The response of the marking device to the action of the spring motive means is normally prevented by an escapement. This escapement comprises a ratchet segment 18 secured to the arm 28 and thus operatively related to the spring motive means. An escapement pawl 19 operatively engages theteeth of the ratchet segment and when the pawl is released the segment is permitted to move a distance corresponding to the tooth pitch of the ratchet. A spring 20 normally holds the escapement pawl in engagement with the ratchet teeth. A pin 21 is secured to the pawl and when raised permits the ratchet segment and hence the marking device to move a. distance corresponding to the tooth pitch of the ratchet.

An arm 22 secured to the pivoted arma- 1 1 25 will engage the fixed contact 26 and electimes of the beginnin metered it is necessary ture 23 of an electromagnet24 engages beneath the pin 21, and operates to raise the pin and release the escapement when the electromagnet'is energized. The circuit of the winding of the electromagnet is completed when the movable contact 25 engages a fixed contact 26.. The movable contact is mounted on a gear member 27 which is rotated by the shaft 6 of the electric meter. Each time that a predetermined quantity of energy has been consumed in the translating devices 10 and metered the movable contact tromagnet 24 will be energized. The escapement pawl 19 is thereupon released and the marking device imparts a short transverse mark on the time actuated record sheet.

The remaining features ofconstruction of my novel graphic recording apparatus will be best understood from a description of the operation thereof. When the marking device is in its zero or initial position the marking means 15 will be positionedover the zero line indicated by reference character a in the drawings. means remains stationary and as the record sheet moves, a vertical line such as b is drawn on the record sheet. When the predetermined quantity of electricity has been consumed and metered the electromagnet 24 is energized and the marking device moves .a predetermined distance toward'the left of the fiure, as heretofore explained. A record mark 0 is thereby drawn on the record sheet.

The vertical lines on the record sheet thus indicate the lengths of time required to consume a predetermined amount of electricity, and the horizontal lines indicate the and ending of the consumption of each 0 such predetermined quantities of electricity.

When a definite number of equal and predetermined quantities of energy have been to return the markmg device to its initia position. The means which I have devised for accomplishing this endconstitute an important feature of my invention. A soft iron armature 30 is rigidly securedto the shaft 16 and has its ends operatively arranged within the infiuv ence ofthe pole pieces of magnetizing coils 32. The circuit of the magnetizing coils 32 is closed when a movable contact 33 mount ed on a rotatable gear 34 engages a' fixed contact 35. The gear 34 is rotated by the meter shaft 6, a'nd thus the energizing of the magnetizing coils is controlled by the meter shaft. -When the magnetizing coils 32 are energized the armature 30 will turn to a horizontal position thereby energizingthe spring motive means 29 and moving the its initial position over the line a. It will thus be seen that the periodic releasing of the escapement pawl and the periodic e'n er- The marking gizing of the spring motive means are both controlled by the rotatable meter shaft 6. In the drawings I have represented a construction in which the spring motive means is energized and the marking device returned to its initial position after the metering of six equal and predetermined quantities of energy as determined by the engagement of contacts 25 and 26. In returning to its initial position the marking device imparts along horizontal line at on the record sheet. This distance between any two lines at therefore indicates the length of time required to consume and meter a quantity of energy equal to six of the smaller predetermined and equal quantities of energy.

In Fig. 2 of the drawings I have illustrated a slightly modified form of -my,im proved graphic recording apparatus. In this modification the marking device is returnedto its initial position atthe end of a predetermined interval of time, as for example, at the end of every 15 minutes. The only change" necessary in the construction of Fig. 1 to produce the modification of Fig. 2 is tosubstitute a time actuated movable contact for the meter actuated contact 33 in Fig. 1. This result I accomplish by driving a gear member 44 provided with a movable contact 43 from the clockwork mechanism 13. The contact 43 cooperates with a fixed contact 45 to close the circuit of the magnetizing cdils 32 at the end of equal time intervals. The record obtained by the modification of Fig. 2 is. substantially the same as that obtained by the apparatus of Fig. 1. The long horizontal lines 6 on the record sheet of Fig. 2 are equally spaced and by counting the number of short horizontal lines C between any two lines 6 and interpolating for fractional quantities of the predetermined energy interval the total amount of energy consumed during the time between two engagements of the contacts 44 and 45 can be readily ascertained.

It will be evidentfrom the foregoing description that I have provided an arrang ment of elements in a graphic recorder which coiiperate to form an accurate, simple, and extremely satisfactory type of apparatus. The operation of the marking device by an independent motive means relieves the electric meter of any objectionable external load, since the meter has only to close the contacts in the circuits of the electromagnetic controlling devices. The step by step record is a peculiarly advantageous form in which to record the demand of an electrical installation, and the division of the record into blocks by the periodic return of the marking device to its initial 0- Numerous modl cations in the details of construction of my improved graphic reeorder 'will be obvious to those skilled in the art. I do not, therefore, desire to be limited to the specific arrangement of elements herein shown and described for the purpose of illustrating my invention. 1, accordingly, aim in the appended claims to cover all modifications which are within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is 1. A graphic recording apparatus comprising a movable record sheet, a marking device operatively related to said record sheet,

motive means operatively connected to said marking device and adapted to move the marking device to impart a mark on said record sheet, means whereby said motive means is adapted to impart a periodic move-- ment to said marking device, and means for periodically energizing said motive means whereby said marking device is returned to an initial position.

2. A graphic recording apparatus .comprising a movable record sheet, a marking device operatively related to said record sheet, a spring motive means operatively connected to said marking device and adapted to move the marking device substantially transversely of the direction of movement of the record sheet, means whereby said spring motive means is adapted to impart a periodic movement to said marking device thereby producing a step by step record on the record sheet, and means for periodically energizing said spring motive means whereby said marking device is returned to an initial position.

3. A graphic recording apparatus comprising a movable record sheet, a marking device operatively related to said record sheet, a sprin motive means operatively connected to said marking device, an escapement operatively related to said spring motive means and adapted when released to permit a certain movement of the marking device in response to the action of the spring motive means, means whereby said escapement is periodically released, and means for periodically energizing said spring motive means whereby said marking device is returned to an initial position.

4. A graphic recording apparatus comprising a movable record sheet, a marking device operatively related to said record sheet, a spring motive means operatively connected to said marking device, a ratchet operatively related -to said spring mo ive means, an escapement fpawl adapted when released to permit the ratchet to move in response to the spring motive means a distance corresponding to the tooth pitch of theratchet, means whereby said escapement is periodically released, and means for periodically energizing said spring motive means whereby said marking device is returned, to an initial position.

5. The combination with an electric meter of a time actuated record sheet, a marking device operatively related. to said record sheet, motive means operatively connected to said marking device, means whereby said motive means impart a periodic movement to said marking device, and means for periodically energizing said motive means whereby said marking device is returned to an initial position. i

- 6. The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said record sheet, motive means tending to move said marking device, an escapement operatively related to said motive means, means for periodically releasing said escapement whereby a mark is produced on said record sheet, and means for periodically energizing said motive means whereby said marking device is returned to an initial position. 7 The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said record sheet, means for moving said marking device a predetermined distance at the end of the metering of each of a number of equal quantities of energy whereby a step by step record is produced on said record sheet, and means for returning said marking device to an initial osition at the end of the metering of a pre etermined number of said equal quantities of energy.

8. The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said record 'of a number ofiequal quantities of energy whereby a step.-;by*step record is produced on said record-sheet, means operatively re lated to said motive means and adapted when actuateditoenergize the motive means and to return the marking device to an initial position, and means r actuating said last mentioned means at the end of the me tering of a predetermined number of said equalquantities of energy.

9. The combination with an electric motor havin a rotatable shaft of a time actuated recor sheet, a marking device operatively related to said record sheet motive means operatively connected to sa d markm vice, means operatively related to sm mo- 130 tive means and controlled by the meter shaft whereby a periodic movement is imparted to said marking device, and means for periodically energizing said motive means whereby said marking device is returned to an initial position.

10. The combination with an electric meter having a rotatable shaft of a time actuated record sheet, a marking device operatively related to said record sheet, motive means operatively connected to said marking device, means operatively related to said motive means and controlled by the meter shaft whereby the motive means imparts a periodic movement to said marking device, and means controlled by the meter shaft for energizing said motive means whereby said marking device is periodically returned to an initial position.

11. The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said-record sheet, motive means .operatively connected to said marking device, means whereby said motive means imparts a'movement to said marking device at the end of the metering of each of a number of predetermined and equal quantities of energy, and means for periodically energizing said motive means whereby said marking device is returned to an initial position.

12. The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said record sheet, motive means operatively connected to said marking device, an escapement op eratively related to said motive means, means for releasing said esca )ement at the end of the metering of each 0 a number of predetermined and equal quantitiespf energy whereby saidmotive means imparts a periodic movement to said markin device, and means for periodically energizing said motive means whereby said marking device is returned'to an initial position.

13. The combination with an electric meter of a time actuated record sheet, a marking device operatively related to said record sheet, a spring operatively connected to said marking device and adapted to move the marking device to impart a mark on the record sheet, an escapement operatively related to said spring and adapted to prevent the response of the marking device to the action of the spring, means for periodically releaslng said escapement, and means for periodicall y energizing said spring whereby said marking device is returned to an initial position. v

' 14. The combination with an electric meter having a rotatable shaft of a time actu ated record sheet, a marking device operatively related to said record sheet, a spring operatively connected to said marking device. and adapted to move the marking device to impart a mark on the record sheet, an escapement operatively related to said spring and adapted to prevent the response of the marking device to the action of the lated to said spring motive means, an escapement pawl adapted when released to permit the ratchet to move in response to the action of the spring motive means a distance corresponding to the tooth pitch of the ratchet, means controlled by the meter shaftfor releasing the escapement at the end of the metering of each of a number of equal quantities of energy whereby a step by step record is produced on the record sheet, electroresponsi've means operatively related to said spring motive means and adapted when actuated to energize the spring motive means and to return the marking device to an initial position, and means controlled by the meter shaft for actuating said electroresponsive means at the end of the metering of a predetermined number of said equal quantities of energy.

In witness whereof, I have hereunto set my hand this 18th day of October, 1913.

J OHN T. DEMPSTER.

Witnesses HELEN ORroRn, Man WEISBROD.- 

